Bag closer and sealer



Aug. 1965 s. T. ADAMS ETAL 3,200,558

BAG CLOSER AND SEALER Filed Sept. 25, 1962 5 Sheets-Sheet 1 FIG.

INVENTORS swam-4 7.- 4.04: 2/61 2? 155-545 5 Sheets-Sheet 2 Q Q mm I r f N? U NF T m S. T. ADAMS ETAL BAG CLOSER AND SEALER ,c IA.

w 0J" A u N 1, u o o Aug. 17, 1965 Filed Sept. 25, 1962 Aug. 17, 1965 s. 'r. ADAMS ETAL 3,200,553

BAG CLOSER AND SEALER Filed Sept. 25, 1962 5 Sheets-Sheet :5

INVENTORs 54/1054 77 404;

W (FM Aug. 17, 1965 Filed Sept. 25, 1962 BAG CLOSER AND SEALER S. T. ADAMS ETAL 5 Sheets-Sheet 4 lllll l l ll II II Imp W ,2

INVENTORS 54/1054 2- 4m:

Aug. 17, 1965 s. T. ADAMS ETAL 3,200,558

BAG CLOSER AND SEALER Filed Sept. 25, 1962 5 Sheets-Sheet 5 sasasss BAG ICLUSERA'ND SEALER Samuel'I, Adams, New (Means, and Richard P. Kessler,

Metairie, La.; said Kessler and the heirs of said Samuel T. Adams, deceased, assignors to West Virginia Pulp and Paper Company, New York, N.Y., a corporation of Delaware Filed Sept. 25,1962, Ser. No, 226,187

3 Claims. '(CI. 53-76) This device relates to bags.

a device for closing and sealing The primary object of the present invention is topro- 'vide a device which will simply and effectively close and a seal multi-wall' paper bags, of the commonly-termed pinched endf type, after these bags have been filled.

I of the bag shown in FIGURE ZA showing the sealed bag emerging from the final set of press rolls.

FIGURE 3 is a top view of the closing and sealing deviceof FIGURE 1..

FIGURE 4 is a front view of the closing and sealing device of FIGURE 1.

FIGURE 5 is a right end View of the closing and sealing device of FIGURE 1 showing the forward end of the device. A

FIGURE 6 is a left end view of the closing and sealing device of FIGURE 1 showing the rearward end of the device.

FIGURE 7 is a detailed top view of the folder portion of the closing and sealing device shown in FIGURE 1.

FIGURE 8 is a detailed front view of the folder portion shown in FIGURE 7. I

In the preferred embodiment illustrated in the drawings 10 and 10' are flat mounting plates spaced an essentially equal distance apart along their entire length, thereby forming slot 12 through which the bag to be closed and sealed will travel. Mounting plate 10' is supported by a suitable supporting structure 11 which is best shown in FIGURE 6. Mounting plate 10 is in turn adjustably suspended from mounting plate 10' through bridge 14 at 7 its forward end and by frame blocks 15, 16 and 17 through bolts 18 and 19 at its rearward end.

Bridge 14 is connectedto mounting plates 10, 10' through bridge uprights 13, 13. Sliding of bridge 14 'relative to upright 13 is achieved by connecting upright 13 to bridge 14 through a lengthwise slot 45. Biasing of the uprights 13, 13 toward each other by means of bridge spring 43 permits slot 12 to be normally maintained at a uniform width but capable of being opened wider at the forward end thereof in order to permit removal of a bag from the mechanism in case of a'malfunction or release United States Patent 0 aasassa Patented Aug. 17, 1965 25 for delivery to adhesive to applicator head 23, and a valve 24 for on-oif control of the flow of adhesive to applicator head 23. The adhesive applicator assembly is supported by arm 27 which is pivotably mounted on post 26 which in turn is rigidly fastenedto mounting plate 10. A helical spring 28 is also mounted on post 26 so as to bias the 'arm 27 in a clockwise direction as seen from above as in FIGURE 3.

Valve 24 pneumatically. controlled by an actuating means comprising rod 29, air cylinder 30, air lines 31 and 32, and solenoid valve 33. These components are so arranged that, as solenoid valve 33 is opened, air pressure will be supplied from air line 32 to air cylinder 30 through air line 31. The air pressure in the air cylinder 30 will push rod 29 axially, causing valve 24 to open. When solenoid valve 33'is closed, the air pressure in line 32'will be shut off from air cylinder 30 and the air therein permitted to bleed out through the solenoid valve 33. As the air pressure in air cylinder 30 is reduced, the adhesive in line 25, which is also under pressure, will act on the opposite side of valve 24 to cause it to close and stop the flow of adhesive to applicator'head 23. To permit rapid and clean operation of valve 24, the adhesive in line 25 should be at a pressure of at least 10 pounds per square inch above atmospheric pressure and the air pressure supplied to air cylinder 30 should be at a pressure at least10p.s.i. higher than the adhesive pressure. Very satisfactory resultshave been achieved using about 25-40 p.s.i.g. 'adhesive pressure and 70100 p.s.i.g. air pressure.

Solenoid valve 33 is controlled by microswitch 34 through wire 35 connecting these parts. The signal generated in the microswitch 34 is developed by movement of sensing arm 37 during the passage of the bag 22 through slot 12. The position and length of sensing arm 37 and microswitch 34 are so adjusted that the micro switch will activate solenoid valve 33' to an open position at the same time as the leading edge of the bag 22 reaches a position even with applicator head 23. As the trailing edge of the bag 22 approaches application head 23, sensing arm 37 is also so adjusted and biased that it will slip off of the trailing edge and return to its normal position as shown in FIGURE 3, thereby generating a signal in the microswitch 34 causing solenoid valve 33 toclose and stopping the flow of adhesive through valve 24.

Just rearward of the adhesive applicator assembly is located a folder 33. The folder 38, which is mounted along the edge of mounting plate 10' adjacent slot 12, comprises a shaped metal sheet so curved that as the bag passes beneath it a portion of the top of the bag is folded through 90 and then progressively bent through an angle of an operators hand should it become inadvertently caught in the machinery.

' Guides 20 and 20 are mounted on mounting plates 10, 10' respectively. These guides are located at the edges of the mounting plates adjacent to slot 12 and serve to guide the top portion of the bag 22 into slot 12.

An adhesive applicator assembly is positioned just beyond the rearward end of guide 20. This adhesive applicator assembly comprises an applicator head 23 for applying the adhesive to the bag, an adhesive supply line of and folded back against the side of the bag which has just received at least one strip of adhesive from the applicator head 23 as is shown in FIGURE 23. An extension 47 of the top edge of guide 20 serves as a mandrel in cooperation with the folder 38 during the folding operation.

Also. mounted on mounting plates 10 and 10 immediately to the rear of folder 38 is a pair of opposing rolls 40, 40'. These rolls are driven through the power train comprising gears 42, 42', 44, 46 and 46, shaft 48, pulley 50, and belt 52 connected to power source 54. The pressure of rolls 4i and 40 against one another can be adjusted by tightening or loosening nut 62 on rod 19. Such movement of nut 62 will alter the compression on spring 64 which presses against mounting block 17. Such pressure in turn will be transferred to the shaft of roll 40 which passes through block 17.

tion of the bag. This stepping is necessary due to the difference in the thicknessin the folded bag end in the side or gusset areas of the bag because of the variance in the number ;o'f-plies"of papergin those areas-relative to the remainder "ofgthe bag. The pressure between rolls 60 and 60" can be adjusted in a manner similar to that for rolls 40 and 40 by adjusting nut 56 on rod 18 which will change the compression on spring 58 urging mounting block 16 towardrblock 15. In order that the pressure adjustment on rolls 40, Y40' and 60, 60' may be independent of one another, blocks. 16 and 17 are hingeably connected by means of hinge bolt 59 1. A supporting plate 61- is also rigidly attached to blockandpivotably at tached to hinge bolt 55? above blocks 16 and 17 to furnish additional support 'to hinge bolt 59gblocks-16 and 17-, rolls 40 and 60, mounting plateltL-and conveyor belt Movement of the bag 22 through the. sealer and closer is supplied by bag-supporting conveyor 36; Since there is some tendency of the 'top of the bag 22 to lag behind the bottom of the bag which is driven by the conveyor,

opposing belts 39 and 39 are supplied. The surface ries thebottom of the bag while the sides. of the'bag 22 p are pressed together and flattened during passage through slot 12. I

In the operation of the closing and sealing device described, the filled bag 22 is placed on the right-hand end of the bag-supporting conveyor-:36. The movementof conveyor 36 carries the bag between guides'20 and 20 whichcenters the topof the bag 22 in slot 12. As the bag 22 reaches the right hand-end of belts 39, 39', it is grasped between these belts which are travelling at the same surface speed as the conveyor, thus insuring uniform .motion of the entire 'bag through the closer and sealer. As the bag travels through slot 12 it will contact sensing arm 37. Further movement of the bag 22 will cause sensing arm 37 torotate until apoint is reached where the .microswitch 34 is tripped, actuating the solenoid valve 33 which in turn admits airto air cylinder 30 sothat rod 29 is pushed, opening valve 24 and starting the. flowof adhesive.

Due to the pivotable mounting of the adhesive applicator assembly on post 26 and the bias provided by spring 28, applicator head 23 is maintained in constant contact with the bag surface in spite of irregularities in the bag surface and thickness of the bag dueto the difference, in

the number of plies.

As the trailing edge of the bag approaches the applicator head 23, the sensing arm 37 will slip off the trail ing edge of the bag. .The bias placed on the sensing arm 37 will cause it to return toits normal position, thus actuating the microswitch 34 and solenoid valve 33 to close valve 24.

It is important in the formation of the bags that the paste be applied across the entire width of the bags. It

i is particularly important that the paste'be applied right up to the edges of the bag to prevent improper sealing at these critical points which would permit sitting of the contents and provide a weak point for rupture during handling of the filled bag.

cator head 24 when thebag-does not cover the head as this will tend to clog the machine. the flow of paste must begin at the instant the leading edge 'ofthe bag passes applicator head 24 and must of sensing arm 37 and the flow of paste from applicator It is likewise important, however, that the paste not be extruded through appli-' For these reasons configuration such that the flow of'paste is started and stopped at the correct time. w

Afterthe application of adhesive to bag 22 as a smeared strip 55, it passes through thefolde'r' 38 wherein the top portion of the bag is folded downialong a line just above the area to which the adhesive was applied. As the bag passes between rolls 40 and 40, the pressure .of these. rolls causes the pasteto. spread; Final sealing'is'accomplished when the bag passesbetween rolls wand 60'. Rollsy60 and 6 0' are stepped, with the, individual steps being about 0.01 to 0.05 inch in depth so as to provide morenearly uniform pressure against thefolded portion of the bag which, it will readily be; observed, varies in the number of plies due to the stepped'cutting of the i g It is imperati e that the closer and sealer of this invention be employed in combination witha quick-setting liquid adhesive. At conventional, conveyor speeds, it is necessary to use adhesives which can be made to form ,strongpaper-to-paper bonds within ten seconds. A polyvinyl acetate adhesive having a viscosityof 2,200to 3,000 cps. has been found to beparticularly suitable, permitting freshly closed and sealed bags to emerge from the rolls 60, 60' and topple over from the conveyor 36 onto a cement floor beneathwithout damage. a

'It will be obvious that the embodiment describe hereinbefore maybe modified considerably within the framework of the present invention bythose skilled in the art. e

We claim:.; J 7

y 1. A machine for closing and sealing the tops of partially filled-multi-wall paper bags of the pinched-end type which have a freeboard area above the contents, comprising, in combination: p 1

(a) a bag-supporting conveyor upon which the'bags in. upright position travel edgewise through said machine, v

(b) mounting plates spaced apart and defining a frame slot therebetween which is parallel'to andsomewhat less than the height of.a partially filled bag above said conveyor, said mounting plates being biased into parallel position and hingeably separable .at their forwardends, where bags enter said frame slot while being'carried on said bag-supporting conveyor,

7 (c) upper conveyingbelts, each belt being rotatably supported beneath a mounting plate in opposed relationship so as to define cooperatively a hingeably separable slot beneath said frame slot, said' upper conveying'beltsbeing adjusted to travel at the same surface speed 'asthe bag-supporting conveyor and being adapted to grasp the sides of a bag in the freeboard area when the bag enters said frame, slot, whereby the freeboard area of the bag is flattened, guided, and propelled at the same speed as the filled portion of the bag, i r

(d) adhesive deposition meansfor smearingly depositing a strip of adhesive above said conveying. belts and from leading edge to. trailing edge on one side of the flattened-bag, V p

(e) means for accurately :sensing the forwardedges of .a flattened bag, when said :forward. edges are brought by the;bag-supporting conveyor and the upper conveyingbelts into imminent juxtaposition with'the, deposition means, comprising a, bendable elongated sensing arm which is attached atone end to permit sweeping motion in a plane parallel to the bag-supporting conveyor and which is so positioned, immediately beneath the upper. conveying belts 'athwart the path of travel or said bag, that the unattached end of said sensing arm is contacted by the leading edge of the flattened freeboard area of the upright bag and pivotably deflected thereby,

(f) actuating meanswhich cooperate with the sensing means and control the flow of adhesive from the adhesive deposition means, whereby adhesive is delivered to the flattened surface of the bag along one side thereof at the instant that the leading edge appears in juxtaposition with said adhesive deposition means,

(g) means for folding a multi-wall paper strip at the top of one side of the bag over the other side having a strip of adhesive applied thereto;

(h) Pressure-applying means for compressing the folded-over paper strip against the side of the bag having the adhesive strip applied thereto.

'2. A machine for closing and sealing the tops of partial- -ly filled multi-wall paper bags of the pinched-end type which have a freeboard area above the contents, comprising, in combination:

(a) a bag-supporting conveyor upon which the bags in upright position travel edgewise through said machine,

(:b) mounting plates spaced apart and defining a frame slot therebetween which is parallel to and somewhat less than the height of a partially filled bag above said conveyor, said mounting plates being biased into parallel position and hingeably separable at their forward ends, where bags enter said frame slot while being carried on said bag-supported conveyor,

(c) upper conveying belts, each belt being rotatably supported beneath a mounting plate in opposed relationship so as to define cooperatively a hingeably-separable slot beneath said frame slot, said upper conveying belts being adjusted to travel at the same surface speed as the bag-supported conveyor and being adapted to grasp the sides of a bag in the freeboard area when the bag enters said frame slot, whereby the free'board area of the bag is flattened, guided, and propelled at the same speed as the filled portion of the bag,

(d) an adhesive applicator assembly, comprising:

(1) an applicator head for application of liquid adhesive under pressure to the paper surface of the bag,

(2) an adhesive valve for on-oif control of adhesive flow to said applicator head, said valve being opened by air under pressure and closed by liquid adhesive under pressure,

(3) an adhesive supply line for delivery of adhesive under pressure to said valve, said adhesive applicator assembly being supported by an arm which is pivotably attached to one of the mounting plates and biased toward said frame slot,

(e) means for accurately sensing the forward edges of a flattened bag, when said forward edges are brought by the bag-supporting conveyor and the upper conveying belts into imminent juxtaposition with the adhesive applicator, comprising a bendable elongated sensing .arm which is attached at one end to permit sweeping motion in a plane parallel to the bag-supporting conveyor and which is so positioned, immediately beneath the upper conveying belts athwart the path of travel of said bag, that the unattached end of said sens-ing arm is contacted by the leading edge of the flattened freeboa-rd area of the upright bag and pivotably deflected thereby,

(f) actuating means, in cooperation with the sensing means, to open and close said adhesive valve as the leading and trailing edges of a flattened bag are sequentially sensed by said sensing means, whereby the applicator head applies a strip of adhesive from the leading edge to the trailing edge of the bag, comprising,

(l) a microswitch mechanically attached to said g) means for folding a multi-wall paper strip at the top of the freeboard are-a of the bag over a lower portion which has had a strip of adhesive applied thereto from one edge to the other;

(h) pressure-applying means for compressing the folded-over strip against the portion to which adhesive hasbeen applied, whereby the adhesive is set and the top of the bag is quickly sealed along its entire width, said pressure-applying means comprising: l

(1) an elongatedmounting block which is longitudinally aligned with the frame slot and in direction of travel of the bag-supporting conveyor relative thereto,

(2) a pair of hinged mounting blocks forming an elongated block when aligned end-to-end in normally parallel relation to the elongated mounting block and outwardly pivotable therefrom on a center hinge which is rigidly attached tosaid elongated mounting block, each hinged mounting block having a transverse slot in its unattached end,

(3) a forward pair of pressure-applying rolls which form a forward roll nip therebetween, each roll being rigidly and axially attached to a roll shaft, one roll shaft rot-atably transpiercing the elongated mounting block near the forward end thereof and the other roll shaft rotatably transpiercing one of the hinged mounting blocks,

(4) a rearward pair of pressure-applying rolls which form a rearward roll nip therebetween in alignment with the forward hip and with the frame slot, each roll being rigidly and axially attached to a roll shaft, one roll shaft rotatably transpiercing the elongated mounting block near the rearward end thereof and the other roll shaft rotatably transpie-rcing the other of the hinged mounting blocks,

(5 a forward pair of gears which form a gear-type nip thereb-etween, each gear being rigidly and axially attached to a roll shaft of the forward pair of pressure-applying rolls, and each gear and roll on a common shaft being on opposite sides of a transpierced mounting block,

(6) a rearward pair of gears which form a geartype nip therebetween, each gear being rigidly and axially attached to a roll shaft of the rearward pair of pressure-applying rolls, and each gear and roll on a common shat-t shaft being on opposite sides of a transpierced mounting block,

(7) a transmitting gear rotatably attached to the elongated mounting block and forming gear-type nips on opposite sides with a gear of the forward and rearward pairs of gears, whereby rotary motion is transmitted substantially simultaneously to every roll in the forward and rearward pairs of pressure-applying rolls from .a power source connected to one of the gears,

(8) pressure shafts attached transversely to each end of the elongated mounting block and pass ing through the transverse slots in the unattached end of the hinged mounting blocks, and

(9) spring means attached to the pressure shafts adhesive deposition means, whereby adhesive is which urge the hinged mounting blocks toward delivered at the inst-ant that the leading edge of the the elongated mounting block, whereby the gearbag appears in juxtaposition With said adhesive deptype nips function as fulcrums and the roll shafts osition means, 7 rotatably passing through the hinged mounting (f) sensing means cooperatively attached to said acb-locks function as levers to maintain pressure in tuating means for accurately sensing the forward edge the roll nip. of the flattened bag, When said forward edge is 3.-A machine for closing and sealing the top of a parbrought by the bag-supporting conveyor and the tially filled multi-W-a-ll paper bag of the pinched-end type upper conveying belts into imminent juxtaposition which has a freeboard area above the contents and which with the adhesive deposition means, comprising an travels through said machine on a bag-supporting conadjustable elongated sensing arm having a free end veyor, comprising, in combination: to permit motion of said armin a plane parallel to the (a) a supporting structure, bag-supporting conveyor and which is so positioned,

(b) mounting plates, attached to said supporting strucimmediately beneath the upperconveying belts across ture and spaced apart to' define a slot therebetween the path of travel of the bag, that the free end of said which is parallel to and somewhat less than the height sensing arm is contacted by the leading edge of the o f a partially filled bag above said bag-supporting flattened freeboard area of the upright-bag and'pivotconveyor, said rnounting plates being biased into ly deflected y, 1 parallel position and hingedly separable at their for- (g) d g ans m unted 0n said mounting plates ward'ends where bags enter said slot while being r olding a top portion of the freeboard area of carried onsaid bag-supporting Conveyor, the bag against a portion of the remaining ,freeboard upper conveying belts, each belt being rotatably supported beneath amounting plate in opposed relationship and so arranged that the top of the filled area of the bag'whereby the adhesive is enclosed between the tWo portions, and j (h) pressure-applying means mounted on said mountbag in'the, freeboard area above the contents is grasped between the adjacentsurfaces of said belts and carried through the machine at the same speed as that at which the conveyor carries the bottom of the bag while the sides of .the bag are pressed together and flattened during their passage through ing plates for compressing the said two portions to seal the bag.

References Cited by the Examiner UNITED STATES PATENTS said 1 r 2,700,260 1/55 Paulsen 53383 X (d) adhesive deposition means mounted on one of said 2948098 8/60 Hanson et 53383 X mounting plates above said conveyin b l f 2,996,858 8/61 Swanson 3 X smearingly depositing a strip of adhesive from the leading edge to the trailing edge of the bag,

(e) actuating means mounted on one of said mounting plates to control the flow of adhesive from the FRANK E. BAILEY, Primary Examiner.

TRAVIS s. MACGEHEE, Examiner. 

1. A MACHINE FOR CLOSING AND SEALING THE TOPS OF PARTIALLY FILLED MULTI-WALL PAPER BAGS OF THE PINCHED-END TYPE WHICH HAVE A FREEBOARD AREA ABOVE THE CONTENTS, COMPRISING, IN COMBINATION: (A) A BAG-SUPPORTING CONVEYOR UPON WHICH THE BAGS IN UPRIGHT POSITION TRAVEL EDGEWISE THROUGH SAID MACHINE, (B) MOUNTING PLATES SPACED APART AND DEFINING A FRAME SLOT THEREBETWEEN WHICH IS PARALLEL TO AND SOMEWHAT LESS THAN THE HEIGHT OF A PARAITLLY FILLED BAG ABOVE SAID CONVEYOR, SAID MOUNTING PLATES BEING BIASED INTO PARALLEL POSITION AND HINGEABLY SEPARABLE AT THEIR FORWARD ENDS, WHERE BAGS ENTER SAID FRAME SLOT WHILE BEING CARRIED ON SAID BAG-SUPPORTING CONVEYOR, (C) UPPER CONVEYING BELTS, EACH BELT BEING ROTATABLY SUPPORTED BENEATH A MOUNTING PLATE IN OPPOSED RELATIONSHIP SO AS TO DEFINE COOPERATIVELY A HINGEABLYSEPARABLE SLOT BENEATH SAID FRAME SLOT, SAID UPPER CONVEYING BELTS BEING ADJUSTED TO TRAVEL AT THE SAME SURFACE SPEED AS THE BAG-SUPPORTING CONVEYOR AND BEING ADAPTED TO GRASP THE SIDES OF A BAG IN THE FREEBOARD AREA WHEN THE BAG ENTERS SAID FRAME SLOT, WHEREBY THE FREEBOARD AREA OF THE BAG IS FLATTENED, GUIDED, AND PROPELLED AT THE SAME SPEED AS THE FILLED PORTION OF THE BAG, (D) ADHESIVE DEPOSITION MEANS FOR SMEARING DEPOSITING A STRIP OF ADHESIVE ABOVE SAID CONVEYING BELTS AND FROM LEADING EDGE TO TRAILING EDGE ON ONE SIDE OF THE FLATTENED BAG, (E) MEANS FOR ACCURATELY SENSING THE FORWARD EDGES OF A FLATTENED BAG, WHEN SAID FORWARD EDGES ARE BROUGHT BY THE BAG-SUPPORTING CONVEYOR AND THE UPPER CONVEYING BELTS INTO IMMINENT JUXTAPOSITION WITH THE DEPOSITION MEANS, COMPRISING A BENDABLE ELONGATED SENSING ARM WHICH IS ATTACHED AT ONE END TO PERMIT SWEEPING MOTION IN A PLANE PARALLEL TO THE BAG-SUPPORTING CONVEYOR AND WHICH IS SO POSITIONED, IMMEDIATELY BENEATH THE UPPER CONVEYING BELTS ATHWART THE PATH OF TRAVEL OF SAID BAG, THAT THE UNATTACHED END OF SAID SENSING ARM IS CONTACTED BY THE LEADING EDGE OF THE FLATTENED FREEBOARD AREA OF THE UPRIGHT BAG AND PIVOTABLY DEFLECTED THEREBY, (F) ACTUATING MEANS WHICH COOPERATE WITH THE SENSING MEANS AND CONTROL THE FLOW OF ADHESIVE FROM THE ADHESIVE DEPOSITION MEANS, WHEREBY ADHESIVE IS DELIVERED TO THE FLATTENED SURFACE OF THE BAG ALONG ONE SIDE THEREOF AT THE INSTANT THAT THE LEADING EDGE APPEARS IN JUXTAPOSITION WITH SAID ADHESIVE DEPOSITION MEANS, (G) MEANS FOR FOLDING A MULTI-WALL PAPER STRIP AT THE TOP OF ONE SIDE OF THE BAG OVER THE OTHER SIDE HAVING A STRIP OF ADHESIVE APPLIED THERETO; (H) PRESSURE-APPLYING MEANS FOR COMPRESSING THE FOLDED-OVER PAPER STRIP AGAINST THE SIDE OF THE BAG HAVING THE ADHESIVE STRIP APPLIED THERETO. 